Compostable/degradable food packaging
Biodegradable packaging is made from polymers derived from renewable raw materials instead of oil, such as cellulose, soy protein or milk and especially starch (from vegetable sources such as potato, corn or rice, to make plastarch). Plastarch material is biodegradable after use, and the pulp can be formed into useful shapes by injection moulding or thermoforming followed by drying.
They can decompose in suitable composting conditions of warmth, wet and oxygen into simple chemicals, including carbon dioxide gas (or to methane if oxygen is restricted, as in landfill or an enclosed anaerobic digester).
If material otherwise useful as food is being turned into plastics there is direct competition for growing space and the oil input to those farming practices in fuel and petrochemical sprays should be considered before concluding that bioplastics are 'sustainable'.
Waterproof and heat tolerant PLA plastic packaging made from polylactic acid is transparent and resembles oil-derived PET (polyethylene terephthalate). It is claimed to be compostable, but only with success in anaerobic digesters which are not usually used for packaging materials. PLA packaging (using resin recycling ID code 7) is accidentally mixed with PET (using code1), because of similar appearance, which then makes the PET lower value for recycling and unviable . Read more on the resulting debate.
Starch is used to make paper-plate or bowl substitutes that can be coloured with food dyes, will compost once soiled by food; and starch is also used to make lightweight packaging padding as a polystyrene substitute.
Compostable packaging suppliers
The following is a partial list of compostable packaging suppliers in New Zealand. In providing this list, One Planet
does not endorse or guarantee the suppliers named.
BCS Foodpak Ltd
Elldex Packaging Ltd
Kiwi Greenpak Ltd
Potatopak NZ Ltd
Range of biodegradable products including clamshells, cups and bags
Additions can be made to this supplier list: contact us